Zinium is a miracle of our world - and probably of all the worlds. Found at the close of the XIX-th century during archeological dig on the territory of modern Albania, Zinium belonged to Caesar himself and was lost in his last campaign.
We consider a geographical map with N countries numbered from 1 to N (0 < N < 99). For every country we know the numbers of other countries which are connected with its border. From every country we can reach to any other one, eventually crossing some borders. Write a program which determines whether it is possible to colour the map only in two colours